If you have been following the saga of my attempts to have comments posted at the Huffington Post, I have an update.
Dr Robert Lustig recently published an article in Nature in which he argued that we need to take drastic measures to reduce the consumption of sugar. His is a well-reasoned argument based on evidence that sugar, and the fructose component in particular, is uniquely harmful. Remember that all sugar is 50% fructose and 50% glucose. High Fructose Corn Syrup (HFCS) tends to have a bit more fructose because this is the molecule that delivers the most sweetness. HFCS is typically 55% fructose and 45% glucose. In terms of effect, both sugar and HFCS are the major sources of fructose in our diet and have been increasing in consumption over the decades during which we have been experiencing the twin epidemics of obesity and type 2 diabetes. There is physiological evidence that fructose consumption can be implicated in a number of conditions including insulin resistance, fatty liver, gout and hypertension. Lustig’s article has generated the predictable backlash from the vested interests in the agri-food sector whose bottom lines would be severely affected if people stopped eating all the useless crap they produce and which fills the centre aisles of the supermarket.
Meanwhile, over at HuffPo, Dr David Katz has weighed in with an article entitled, “Sugar, On a Slippery Slope” (http://www.huffingtonpost.com/david-katz-md/sugar-regulation_b_1255695.html), where his basic argument is that the poison is in the dose. He says that it isn’t sugar per se that is a problem but rather that people eat too many calories of which some are sugar. He goes on to vilify diets that exclude the “nutrients du jour”, an obvious dig at low-carb diets.
Here are his own words:
There is no question that excess sugar is one of the great liabilities of the modern diet, and consequently, one of the great liabilities of public health. Excess sugar intake is implicated in everything from obesity to diabetes to coronary artery disease. Because excess consumption of sugar induces hormonal imbalances — notably high levels of insulin — which in turn foster inflammation, excess sugar intake is linked to cancer risk as well. Finding effective ways to reduce ambient sugar intake is not only warranted, but rather urgent — as we confront epidemics of obesity, diabetes and associated chronic diseases.
Wow! That’s pretty damning. I guess he is on our side after all. How can you not be in favour of harsh measures to constrain the consumption of something so obviously toxic to the human body?
Here’s how:
Regulating nutrients, per se, is a slippery slope. If we regulate sugar, we should certainly regulate trans fat — which is far less important to palatability, and more toxic in smaller quantities.
And:
And if so, what about the real culprit in much of what most ails modern public health: calories? The root cause of most diabetes and much other chronic disease is obesity, and the most indelible link between weight and food is not composition, but quantity. If sugar is poison because of the harms of excess, so too — and then some! — for calories. Shall we regulate the quantity of food people eat?
This is a classic reductio ad absurdum argument. In addition, it is based on the faulty studies that tested low-carb diets against other macronutrient variations which concluded that they all delivered the same benefit, or rather, lack of benefit (I will post another discussion on some recent examples of this soon).
And this:
We have decades of dietary debacles to show we are unlikely to get to health one nutrient at a time. It is past time to start thinking about the overall nutritional quality of foods, and diet — which are what truly matter to health outcomes. Sugar is an important component of this, to be sure — but only a component.
And he concludes with this:
We eat too much sugar; doing so conspires against our health, and needs to change. The ends are clear, the best means are less so. I worry that some good intentions could bog us down in conflict that forestalls all progress, distort the relative importance of just one nutrient relative to overall nutrition, and land us on a slippery slope headed toward unintended consequences. The sweet spot will be defined by what works in the real world to improve the quality of prevailing diets, and health.
Now, when I first read this, it immediately occurred to me that the whole piece could have been written by the PR people at Coca-Cola. It so nicely dovetails with the kind of smokescreen they and other sugar-dependent companies send up whenever some science has shed light on the harms of their principle ingredient and profit centre. It’s all very reminiscent of the tactics used by the tobacco industry when their products first came under attack.
In the past, I have had my differences with Dr Katz and have been frustrated at times when my reasoned but pointed comments on his articles are censored (see Ornish Filter posts below). It has always struck me as odd, however, that a fellow MD, knowledgeable about nutrition and chronic disease, Director, no less, of the Yale Prevention Research Center, could be so stubbornly averse to acknowledging the now obvious benefits of dietary carbohydrate restriction. Well today, I think I got my answer. Here is a comment from TinaFxyz that did make it past the censors:
One has to question Dr. Katz’s motives. His “Turn The Tide” foundation
He supports the convention
What he is saying is that candy, soft drinks, fruit juice, refined grains, and other processed and carbo-load
All of those companies listed above are sponsors for his research groups and various business activities – I found all of this informatio
Kaboom! Well, there it is for all to see. Is this guy going to take a public position that is fundamentally against the interests of the corporations that fund his work?
There is a well known concept in the business and academic world known as “conflict of interest”. There is also a lesser known concept in the philosophy of art world known as “corruption of consciousness”. I think they both have relevance here.
I wonder how long TinaFxyz will continue to have her comments published on HuffPo.
Upton Sinclair is said to be the author of this aphorism:
“It is difficult to get a man to understand something when his salary depends upon his not understanding it.”
Perhaps that’s being too charitable to Dr. Katz.
When things don’t make sense superficially, it often helps to “follow the money.” If you can find the trail.
-Steve
Dr Jay’s Reply:
In a nutshell!
In response to HLIB’s questions and concerns about LCHF the new book, The Art and Science of Low Carb Living by Phinney and Volek may provide the answers. It certainly clarified some similar issues for me.
Dr Jay’s Reply:
I agree. I think it is the best book on LCHF currently available. Volek and Phinney are currently working on some other projects so it will be interesting to see what else they come up with.
From a biochemist’s point of view, Lustig’s article is a mix of opinion and superficial understanding of science. As I posted on Facebook (weight of the evidence): What we know is that if you have a high carbohydrate diet and you substitute some fructose for glucose or challenge with fructose vs. glucose, the results are bad — although frequently not as dramatic as if you replace carbohydrate across the board with fat. At lower levels of total carbohydrate, the results are more complicated. Remember fructose can be turned into glucose. That’s why the glycemic index of fructose is 20 and not zero. One of the problems with the biochemistry presented by the fructophobes is that many of the pathways that were shown were studied in rodents and you have to be careful about generalizing. Fructophobia is part of lipophobia and is a smoke-screen for not facing low-carb. Remember, the USDA is down on SOFA — solid fat and added sugar (I awarded this SAY, stupidest acronym of the year). Lustig is at great pains not to say that fructose is a carbohydrate — hence his saying “ethanol is a carbohydrate,” the indicator that nothing he says can be trusted. Ethanol is not a carbohydrate.
Dr Jay’s Reply:
Welcome to my blog. Your thoughtful comments are appreciated. And, in matters biochemical, I certainly defer to your knowledge and expertise. I do agree that ethanol is not a carbohydrate (this, thankfully, is why a little distilled spirit or a glass of wine is okay on my version of a LCHF diet). However, I don’t see the fructophobes and lipophobes as one and the same as I certainly identify more with the former than with the latter. While I am more in agreement than you are with the argument Lustig makes in Nature, I don’t for a minute think that his editorial is going to result in taxes on sugar and government imposed restrictions on its access. However, by staking out a fairly extreme position, I do see him raising awareness and expanding the discussion, neither of which are bad things. Clearly we need more research to tease out whether it is fructose or refined carbs in general that is driving our chronic disease epidemics. A three-arm study comparing low-carb, low-fructose and control diets would be a good start. There will still be the problem of the use of these diets as therapy for a damaged metabolism vs their applicability in primary prevention. That would take more effort to sort out, obviously. In the meantime, I don’t fault Lustig for his attacks on sugar as it moves the discussion in the right direction irrespective of whether the ultimate destination is going to be a sugar-free, fructose-free or carb-free diet.
In case you haven’t seen it yet, here is an interesting graph of US sugar consumption that Stephan Guyenet recently posted on his blog: